Structural aspects of face recognition and the other-race effect

The other-race effect was examined in a series of experiments and simulations that looked at the relationships among observer ratings of typicality, familiarity, attractiveness, memorability, and the performance variables ofd’ and criterion. Experiment 1 replicated the other-race effect with our Caucasian and Japanese stimuli for both Caucasian and Asian observers. In Experiment 2, we collected ratings from Caucasian observers on the faces used in the recognition task. A Varimax-rotated principal components analysis on the rating and performance data for the Caucasian faces replicated Vokey and Read’s (1992) finding that typicality is composed of two orthogonal components, dissociable via their independent relationships to: (1) attractiveness and familiarity ratings and (2) memorahility ratings. For Japanese faces, however, we fond that typicality was related only to memorahility. Where performance measures were concerned, two additional principal components dominated by criterion and byd’ emerged for Caucasian faces. For the Japanese faces, however, the performance measures ofd’ and criterion merged into a single component that represented a second component of typicality, one orthogonal to thememorability-dominated component. A measure offace representation quality extracted from an autoassociative neural network trained with a majority of Caucasian faces and a minority of Japanese faces was incorporated into the principal components analysis. For both Caucasian and Japanese faces, the neural network measure related both to memorability ratings and to human accuracy measures. Combined, the human data and simulation results indicate that the memorahility component of typicality may be related to small, local, distinctive features, whereas the attractiveness/familiarity component may be more related to the global, shape-based properties of the face.     

Reversibility of the other-race effect in face recognition during childhood

Early experience with faces of a given racial type facilitates visual recognition for this type of face relative to others. To assess whether this so-called other-race effect can be reversed by subsequent experience with new types of faces, we tested adults of Korean origin who were adopted by European Caucasian families when they were between the ages of 3 to 9. The adoptees performed a face recognition task with photographs of Caucasian and Asian faces. They performed exactly like a control group of French participants, identifying the Caucasian faces better than the Asiatic ones. In contrast, a control group of Koreans showed the reverse pattern. This result indicates that the face recognition system remains plastic enough during childhood to reverse the other-race effect.     

Perceptual expertise and the plasticity of other-race face recognition

In this paper, we argue that our ability to recognize own-race faces can be treated as a form of perceptual expertise. Similar to object experts (e.g., birdwatchers), people differentiate own-race faces at the subordinate level of categorization. In contrast, like novices, we tend to classify other-race faces at the basic level of race. We demonstrate that, as a form of perceptual expertise, other-race face recognition can be systematically taught in the lab through subordinate-level training. When participants learn to quickly and accurately differentiate other-race faces at the subordinate level of the individual, the individuating training transfers to improved recognition of untrained other-race faces, produces changes in event-related brain components, and reduces implicit racial bias. Subsequent work has shown that other-race learning can be optimized by directing participants to the diagnostic features of a racial group. The benefits of other-race training are fairly long-lived and are evident even 2 weeks after training. Collectively, the training studies demonstrate the plasticity of other-race face recognition. Rather than a process that is fixed by early developmental events, other-race face recognition is malleable and dynamic, continually being reshaped by the perceptual experiences of the observer.     

The neural plasticity of other-race face recognition

Although it is well established that people are better at recognizing own-race faces than at recognizing other-race faces, the neural mechanisms mediating this advantage are not well understood. In this study, Caucasian participants were trained to differentiate African American (or Hispanic) faces at the individual level (e.g., Joe, Bob) and to categorize Hispanic (or African American) faces at the basic level of race (e.g., Hispanic, African American). Behaviorally, subordinate-level individuation training led to improved performance on a posttraining recognition test, relative to basic-level training. As measured by event-related potentials, subordinate- and basic-level training had relatively little effect on the face N170 component. However, as compared with basic-level training, subordinate-level training elicited an increased response in the posterior expert N250 component. These results demonstrate that learning to discriminate other-race faces at the subordinate level of the individual leads to improved recognition and enhanced activation of the expert N250 component.     

Emotional face expressions recognition in childhood: developmental markers,age and sex effect

Cognitive Processing - Recognizing emotional face expressions in others is a valuable non-verbal communication and particularly relevant throughout childhood given that children’s language...     

The effect of motion at encoding and retrieval for same- and other-race face recognition

In an experimental study, we assessed the role of motion when encoding and recognizing unfamiliar faces, using an old/new recognition memory paradigm. Our findings revealed a clear advantage for learning unfamiliar faces moving non-rigidly, compared with static faces. This advantage for motion was found with both same- and other-race faces. Furthermore, results indicate that it is more important that the face is learnt in motion than recognized from a moving clip. Interestingly, despite a reliable other-race effect being revealed, participants were able to utilize motion information exhibited by other-race faces in a manner akin to the motion advantage found for same-race faces. The implications of these findings are discussed in relation to the nature of the stored face representations, considering whether the facilitative role found here can be explained by factors other than motion per se.     

The social-encoding benefit in face recognition is generalized to other-race faces

Faces are visual stimuli that convey rich social information. Previous experiments found better recognition for faces that were evaluated based on their social traits than on their perceptual features during encoding. Here, we ask whether this social-encoding benefit in face recognition is also found for categories of faces that we have no previous social experience with, such as other-race faces. To answer this question, we first explored whether social and perceptual evaluations for other-race faces are consistent and valid. We then asked whether social evaluations during encoding improve recognition for other-race faces. Results show that social and perceptual evaluations of own- and other-race faces were valid. We also found high agreement in social and perceptual evaluations across individuals from different races. This indicates that evaluations of other-race faces are not random but meaningful. Furthermore, we found that social evaluations facilitated face recognition regardless of race, demonstrating a social-encoding benefit for both own- and other-race faces. Our findings highlight the role of social information in face recognition and show how it can be used to improve recognition of categories of faces that are hard to recognize due to lack of experience with them.     

The contribution of shape and surface information in the other-race face effect

Faces from another race are generally more difficult to recognize than faces from one's own race. However, faces provide multiple cues for recognition and it remains unknown what are the relative contribution of these cues to this “other-race effect”. In the current study, we used three-dimensional laser-scanned head models which allowed us to independently manipulate two prominent cues for face recognition: the facial shape morphology and the facial surface properties (texture and colour). In Experiment 1, Asian and Caucasian participants implicitly learned a set of Asian and Caucasian faces that had both shape and surface cues to facial identity. Their recognition of these encoded faces was then tested in an old/new recognition task. For these face stimuli, we found a robust other-race effect: Both groups were more accurate at recognizing own-race than other-race faces. Having established the other-race effect, in Experiment 2 we provided only shape cues for recognition and in Experiment 3 we provided only surface cues for recognition. Caucasian participants continued to show the other-race effect when only shape information was available, whereas Asian participants showed no effect. When only surface information was available, there was a weak pattern for the other-race effect in Asians. Performance was poor in this latter experiment, so this pattern needs to be interpreted with caution. Overall, these findings suggest that Asian and Caucasian participants rely differently on shape and surface cues to recognize own-race faces, and that they continue to use the same cues for other-race faces, which may be suboptimal for these faces.     

Why the other-race effect matters: Poor recognition of other-race faces impacts everyday social interactions

What happens to everyday social interactions when other-race recognition fails? Here, we provide the first formal investigation of this question. We gave East Asian international students (N = 89) a questionnaire concerning their experiences of the other-race effect (ORE) in Australia, and a laboratory test of their objective other-race face recognition deficit using the Cambridge Face Memory Test (CFMT). As a ‘perpetrator’ of the ORE, participants reported that their problems telling apart Caucasian people contributed significantly to difficulties socializing with them. Moreover, the severity of this problem correlated with their ORE on the CFMT. As a ‘victim’ of the ORE, participants reported that Caucasians' problems telling them apart also contributed to difficulties socializing. Further, 81% of participants had been confused with other Asians by a Caucasian authority figure (e.g., university tutor, workplace boss), resulting in varying levels of upset/difficulty. When compared to previously established contributors to international students' high rates of social isolation, ORE-related problems were perceived as equally important as the language barrier and only moderately less important than cultural differences. We conclude that the real-world impact of the ORE extends beyond previously identified specialized settings (eyewitness testimony, security), to common everyday situations experienced by all humans.     

Face value: testing the utility of contextual face cues for face recognition

The presence of multiple faces during a crime may provide a naturally-occurring contextual cue to support eyewitness recognition for those faces later. Across two experiments, we sought to investigate mechanisms underlying previously-reported cued recognition effects, and to determine whether such effects extended to encoding conditions involving more than two faces. Participants studied sets of individual faces, pairs of faces, or groups of four faces. At test, participants in the single-face condition were tested only on those individual faces without cues. Participants in the two and four-face conditions were tested using no cues, correct cues (a face previously studied with the target test face), or incorrect cues (a never-before-seen face). In Experiment 2, associative encoding was promoted by a rating task. Neither hit rates nor false-alarm rates were significantly affected by cue type or face encoding condition in Experiment 1, but cuing of any kind (correct or incorrect) in Experiment 2 appeared to provide a protective buffer to reduce false-alarm rates through a less liberal response bias. Results provide some evidence that cued recognition techniques could be useful to reduce false recognition, but only when associative encoding is strong.     

Affect and face perception: odors modulate the recognition advantage of happy faces

Previous choice reaction time studies have provided consistent evidence for faster recognition of positive (e.g., happy) than negative (e.g., disgusted) facial expressions. A predominance of positive emotions in normal contexts may partly explain this effect. The present study used pleasant and unpleasant odors to test whether emotional context affects the happy face advantage. Results from 2 experiments indicated that happiness was recognized faster than disgust in a pleasant context, but this advantage disappeared in an unpleasant context because of the slow recognition of happy faces. Odors may modulate the functioning of those emotion-related brain structures that participate in the formation of the perceptual representations of the facial expressions and in the generation of the conceptual knowledge associated with the signaled emotion.     

A perspective on the recognition of other-race faces

The purpose of the present study is to provide a perspective on the recognition of other-race faces, i.e., black faces by white subjects. Past research has indicated that individuals have greater difficulty recognizing other-race faces than they do same-race faces. On the basis of previous findings, we chose to investigate the recognition of black faces by white subjects as a function of the quantity and quality of previous experience with blacks, racial attitudes, field dependence/independence, and recognition training. Forty-two white subjects participated in pre-, post-, and delayed recognition tests. Subject data were also collected to explore individual differences in recognition performance. Using multiple regression techniques, it was found that field dependence/independence accounted for the largest proportion of variance in recognition performances; a feature-discrimination training task and past experience with blacks were also found to significantly relate to recognition performance. The applied aspects of these results are discussed.     

Investigating the other-race effect in working memory

People have difficulties in remembering other-race faces; this so-called other-race effect (ORE) has been frequently observed in long-term recognition memory (LTM). Several theories argue that the ORE in LTM is caused by differences in earlier processing stages, such as encoding of ingroup and outgroup faces. We test this hypothesis by exploring whether the ORE can already be observed in visual working memory (VWM)—an intermediate system located between encoding processes and LTM storage. In four independent experiments, we observed decreased performance for outgroup faces compared to ingroup faces using three different VWM tasks: an adaptive N-back task, a self-ordered pointing task, and a change detection task. Also, we found that the number of items stored in VWM is smaller for outgroup faces than for ingroup faces. Further, we explored whether performance differences in the change detection task are related to the classic ORE in recognition memory. Our results provide further evidence that the ORE originates during earlier stages of cognitive processing. We discuss that (how) future ORE research may benefit from considering theories and evidence from the VWM literature.     

Computational perspectives on the other-race effect

Psychological studies have long shown that human memory is superior for faces of our own-race than for faces of other-races. In this paper, we review computational studies of own- versus other-race face processing. Computational models examine the visual challenges of representing the uniqueness of individual faces that vary both within and across demographic categories. These models isolate the visual components of the other-race effect and provide an objective control for socioaffective responses to other-race faces. This control allows researchers to compare and test the role of experience/contact in the other-race effect, using various operational definitions of this theoretical construct. The models show that to produce an other-race effect computationally, biased experience or learning must intervene during the process of feature selection. This implicates the critical importance of “developmental” learning in the other-race effect.     

Neural perspectives on the other-race effect

Psychological studies have long shown that human memory is superior for faces of our own-race than for faces of other-races. In this paper, we review neural studies of own- versus other-race face processing. These studies divide naturally into those focused on socioaffective aspects of the other-race effect and those directed at high-level visual processing differences. The socioaffective studies consider how subconscious bias and emotional responses affect brain areas such as the amygdala, anterior cingulate cortex, and parahippocampal gyrus. The visual studies focus on face-selective areas in the ventral stream, such as the fusiform face area (FFA). In both cases, factors such as experience, familiarity, social/emotional responses, cultural learning, and bias modulate the patterns of neural activity elicited in response to own- and other-race faces.     

Effects of mask use and other-race on face perception,emotion recognition,and social distancing during the COVID-19 pandemic

We tested the effect of mask use and other-race effect on (a) face recognition, (b) recognition of facial expressions, and (c) social distance. Caucasian subjects were tested in a matching-to-sample paradigm with either masked or unmasked Caucasian and Asian faces. The participants exhibited the best performance in recognizing an unmasked face condition and the poorest to recognize a masked face that they had seen earlier without a mask. Accuracy was poorer for Asian faces than Caucasian faces. The second experiment presented Asian or Caucasian faces having emotional expressions, with and without masks. The participants' emotion recognition performance decreased for masked faces. From the most accurately to least accurately recognized emotions were as follows: happy, neutral, disgusted, fearful. Performance was poorer for Asian stimuli compared to Caucasian. In Experiment 3 the same participants indicated the social distance they would prefer with each pictured person. They preferred a wider distance with unmasked faces compared to masked faces. Distance from farther to closer was as follows: disgusted, fearful, neutral, and happy. They preferred wider social distance for Asian compared to Caucasian faces. Altogether, findings indicated that during the COVID-19 pandemic mask wearing decreased recognition of faces and emotional expressions, negatively impacting communication among people from different ethnicities.     

Face to face with an enactive approach: A sensorimotor account of face detection and recognition

The enactive approach to perception describes experience as a temporally extended activity of skillful engagement with the environment. This paper pursues this view and focuses on prosopagnosia both for the light that the theory can throw on the phenomenon, and for the critical light the phenomenon can throw on the theory. I argue that the enactive theory is insufficient to characterize the unique nature of experience specific to prosopagnosic subjects. There is a distinct difference in the overall process of detection (with respect to eye movement sequence) of familiar and unfamiliar faces in prosopagnosia; in contrast, normal subjects use the same scanning strategy when exploring both kinds of faces despite an obvious difference in qualitative character. In light of this limitation I outline a supplemental view basing sensorimotor contingencies upon the establishment and reaffirmation of regularities within the organism as it engages with the environment.     

Reassessing the 3/4 view effect in face recognition

It is generally accepted that unfamiliar faces are better recognized if presented in 3/4 view. A common interpretation of this result is that the 3/4 view represents a canonical view for faces. This article presents a critical review of this claim. Two kinds of advantage, in which a 3/4 view either generalizes better to a different view or produces better recognition in the same view, are discussed. Our analysis of the literature shows that the first effect almost invariably depended on different amounts of angular rotation that was present between learning and test views. The advantage usually vanished when angular rotation was equalized between conditions. Reports in favor of the second effect are scant and can be countered by studies reporting negative findings. To clarify this ambiguity, we conducted a recognition experiment. Subjects were trained and tested on the same three views (full-face, 3/4 and profile). The results showed no difference between the three view conditions. Our analysis of the literature, along with the new results, shows that the evidence for a 3/4 view advantage in both categories is weak at best. We suggest that a better predictor of performance for recognition in different views is the angular difference between learning and test views. For recognition in the same view, there may be a wide range of views whose effectiveness is comparable to the 3/4 view.     

Shape, color and the other-race effect in the infant brain

The 'other-race' effect describes the phenomenon in which faces are difficult to distinguish from one another if they belong to an ethnic or racial group to which the observer has had little exposure. Adult observers typically display multiple forms of recognition error for other-race faces, and infants exhibit behavioral evidence of a developing other-race effect at about 9 months of age. The neural correlates of the adult other-race effect have been identified using ERPs and fMRI, but the effects of racial category on infants' neural response to face stimuli have to date not been described. We examine two distinct components of the infant ERP response to human faces and demonstrate through the use of computer-generated 'hybrid' faces that the observed other-race effect is not the result of low-level sensitivity to 3D shape and color differences between the stimuli. Rather, differential processing depends critically on the joint encoding of race-specific features.